Firefox stores your bookmarks, preferences, and other data on your Firefox profile. For regular operation, a profile must be unlocked. Should the profile get accidentally locked, you will see an error message similar to “Firefox is already running.” We’ll explain in this post how to remove this error message so you can resume using Firefox normally.
How To Fix Firefox is Already Running Error
Users have been troubled by the “Firefox is already running” issue for a long time. It is not necessary for you to restart your system in order to resolve the error, despite what the notice suggests. The nuclear option of choice, though, is a restart if everything else fails. However, we want to prevent it, so first consider these options.
Close all Firefox Process
Some Firefox processes may still be operating in the background if Firefox was not properly closed the last time. The reasons Firefox is already operating are these active processes. Click the Close Firefox button when you see the interface below, and then try opening Firefox again normally.
- If using the Close button (X) to end Firefox doesn’t work, you can also utilise Task Manager, as outlined in the steps below.
- To access Task Manager, right-click on a space in the taskbar and choose it from the menu that displays.
- Navigate to the Processes tab, locate Firefox, then use the menu option to End process to end it.
- After quitting the Firefox process, give it a time before opening the browser again. The error should be gone from your experience now.
Restart Your Computer
To fix the issue, you may also just restart your computer. This can terminate all invisible Firefox processes and provide your machine a clean operating environment. Additionally, it can fix any short-term problems that might be causing Firefox to stop working, close, or open.
Delete the -no-remote Startup Option
Certain Mozilla application startup parameters can be set using command line options. However, this can be the reason why Firefox is operating but not responding.
You can check to see if Firefox opens successfully after starting it with the -no-remote command line option removed.
Get Information Back from a Locked Profile
You might need to use the Profile Manager to establish a new profile and then move your data from the locked profile to the new profile if none of the six options listed above work for you. This is a useful post: Create, delete, or switch Firefox profiles with the Profile Manager.